Posture chair



Feb. 29, 1944.

R. A. CRAMER ET AL POSTURE CHAIR Filed July 20 1942 p Buvcntor; AqyA Cram er/PqyAC/amenfn and HamZdmd/zzme/u (mommy Patented Feb. 29, 1944 UNITED STATE POSTUREV CHAIR Roy A. Cramer, Roy A. Cramer, Jr., and Harold W. Cramer, Kansas City, Mo.

Application July 20, 1942, Serial No. 451,650

2 Claims.

This invention relates to posture chairs, and has for one of its objectsthe production of a sim ple, strong, durable and inexpensive chair, wholly of wood or plastic material," except at points where friction occurs through vertical adjustment of the seat-carrying post, swivel movement of the seat, and rocking movement of the backrest.

Another important object is to produce a base member in which the legs of the chair constitute a hub for the support of the seat-carrying post, as contrasted with the type of structure including a special so-called spider for the support of the post and several instrumentalities for cooperation in dependably securing the legs to the spider.

With the objects named in view, theinvention consists in certain new and useful features of construction and organization as hereinafter described and claimed; and in order that it may be fully understood, reference is to be had to the accompanying drawing, in which:

Figure 1 is a view of a chair embodying the invention shown partly in side elevationand partly in central vertical section.

Figure 2 is a front view of the chair.

Figure 3 is a horizontal section taken on the line III-III of Figure 1.

Figure 4 is a horizontal section taken on the line IV--IV of Figure 1.

Figure 5 is an enlarged fragmentary plan view of the base-member legs in separated relation to disclose more clearly, the recesses in the legs which provide the hub with a central vertical post-receiving passage.

Figure 6 is an inverted plan view of a bracket for the mounting of the seat upon the post.

Figure '7 is a fragmentary perspective view of an angle bar for the support of the back-rest from the seat.

Figure 8 is a fragmentary perspective view of another type of angle bar of wood or equivalent material.

Referring now to the drawing in detail, the base member, identified generally by the reference character I, includes four similar legs 2, having corresponding sides radiating from a common center, each leg at its inner end abutting a side of another leg at the inner end thereof. The legs projecting in directly-opposite directions are laterally-ofiset with respect to each other, but stand in parallel planes, and each pair of parallel legs stand at right-angles to the other pair.

To secure the legs in the positions described, each s p v ded. adj cen its inn r end w h a carrying a spring-advanced locking bolt l2, and

plurality of transverse holes 3 (Figs. 1 and 5), engaged by dowel pins 4, projecting from the inner ends of the abutting legs, the dowel pins being disposed longitudinally with respect to the legs from which they project. To further stiffen and strengthen the hub formed by the legs, similar fillets 5, fit in the angles formed by the legs standing at right angles to each other and are rigidly secured to such legs in anysuitable manner. The outer sides of opposite fillets, as shown, are parallel, but this is unimportant'as said sides may be convex, concave or other contour, and yet, in conjunction with the legs, provide astrong, rigid and durable hub. 7 The hub has a central vertical passage 6, produced by registering recesses in the inner ends of the legs. To further'insure the rigidity of the hub and prevent enlargement of the passage 6 through wear,metal or equivalent-plates I, having central openings registering with the'passage 6, fit against the upper and lower ends of the hub, and have marginal teeth 8 embedded in the hub or may be otherwise secured-thereto, and

they also have collars 9, fitting in the ends of the passage and upon the post, hereinafter identified, as a support for the chair seat. The collars also function to prevent inward slippage or creepage of any leg with respect to theother legs which may be equipped with casters ID, if desired.

The provision in the hub of a radial tube ll,

of a guide-pin l3, completes the base member for the reception of the vertical seat-carrying post M, which extends through the passage 6, and has slidable contact with the collars 9, of the plates 1. The post also has the conventional series of sockets l5, for selective engagement by the looking bolt, and a vertical groove I6, for engagement I by the guide pin, and has a conical upper end and a horizontal circular groove l1, near said end.

The seat [8, which may be of any suitable or preferred type, carries a depending bracket 19, of wood or plastic material, for seating on the post, and in this connection it may be noted that while it is in contemplation to use plastic material as well as wood or in conjunction therewith in the production of the base member, itis to be understood that we do not restrict ourselves to the use of any particular material for such purpose. The use of wood or plastic material is desirable for conservation of metal, lightness, low cost of material and manufacture and quick assembly of parts.

The bracket i9, is also preferably of wood or plast c mate a and. as sho n is comp d of two parallel sides 26, extending from front to rear relative to the seat and secured rigidly thereto, and a central member 2i. The latter is preferably composed of two sections, but may be formed integral with the sides 20. In either case, it is spaced from the bottom of the seat, and has a central vertical socket 22, for swivel mounting on the post. The socket contains a conical cap 23, fitting on the top of the post, and provided with a depending collar 24, externally embracing the post below its cone-shaped end. The cap is of character to minimize friction and Wear so that the seat shall have a stable support and not wobble or tilt.

To guard against dislocation of the seat from the post in the event the chair is lifted by grasping the seat, there is a pin 25, secured in the central member of the bracket l9, and in engagement with the circular groove H, of the post, and

at the lower side of the central member there is a plate 26, having a central opening registering "with the socket 22, and provided with a collar or flange projecting into the latter and embracing the post to prevent wear and enlargement of the socket, the plate being rigidly secured to said central member by means of marginal teeth embedded in said membe or in any other suitable manner.

A vertical clamping bolt 21' extends up through the central member IQ, for clamping engagement with thesubstantially-horizontal arm of an angle bar 29, said arm fitting in the space between said member and the seat. The other arm of said angle bar projects upward back of the seat, and is equipped with a vertically-adjustable bracket 30, upon which the back-rest 3| is pivotally mounted for slight rocking action by pressure or relaxation of pressure on the back-rest by a person occupying the seat, in leaning back or forward, there being means, such as a spring 32', tending to hold the back-rest normally in a substantially-vertical position.

In the preferred construction, the angular bar is of laminated type and composed of thin strips of wood or plastic material, and at the point of juncture of the two arms of the bar, bolts 33 are employed to guard against spreading apart of the strips. To cooperate with the bolts, channeled clips .34 may engage with opposite edges of the bar, certain of the bolts holding the clips in place.

As an alternate structure to the laminated type of bar, an angle bar of wood or the like, comprising two arms 35 and 36, standing at right angles to each other, may be employed. As shown, the upright arm 36 is of increased thickness and bifurcated at its lower end as at 31, and provided near but slightly higher than the bifurcation, with downwardly-angled recesses 38, in its opposite edges. The other arm 35, at its rear end is reduced in width to provide a tongue or tenon 39, fitting and glued or otherwise secured in said bifurcation, and further secured by a cross pin 40, extending through the arm 36, and the tongue of arm 35. The angle bar is further stiffened and strengthened by diagonal braces 4|, engaging the recesses 38 and alined recesses 42 in opposite edges of the arm 35.

While any suitable means for securing the bracket 30, at the desired height on the upright arm of the angle bar, it is desirable, especially in a wood or plastic structure, to either fit a-bolt carried by the said bracket, through one of a series of holes through the bar, or to provide the latter with a vertical slot to receive the bracket. As both methods of adjustment of one part upon another are conventional, no showing or more specific mention thereof is needed.

We claim:

1. In a posture chair, a base comprising a series of four legs, corresponding sides of the legs radiating from a common center, the legs at opposite sides of said center being parallel but oiiset laterally, each leg having dowel pins projecting from its inner end and fitting crosswise in th inner end of an adjacent leg.

2. Ina posture chair, a base comprising a series of legs having corresponding sides radiating from a common center, the legs being connected together at their ends and provided at such ends with vertical arcuate recesses cooperatively arranged to form a vertical cylindrical passage, opposite legs standing in laterally-onset relation but parallel to each other, fillets in the angles between the legs and plates secured to opposite faces of the upper ends of the legs. and provided with collars engaging said passage and with marginal teeth embedded in the legs and fillets.

ROY A. CRAMER. ROY A. CRAMER, JR. HAROLD W. CRAMER. 

